I nominate remove_dir_all by @XAMPPRocky.
You know that remove_dir_all function in std? Yeah, it basically doesn't work on windows, because files with open handles can't be deleted, and there are plenty of situations where this happens unexpectedly.
The remove_dir_all crate tries hard to really delete directories on windows. It is used now by the tempdir crate, and similar code is open-coded within rustup and rust-installer.